1. Field of the Invention
This invention relates to a heating apparatus for hyperthermia, and more particularly to a heating apparatus for hyperthermia for locally heatingly treating a predetermined portion of a living body by use of electromagnetic waves.
2. Description of the Prior Art
In recent years, heating treatment methods (or referred to as "hyperthermia") have been highlighted, and particularly, such research reports have been successively submitted that, for example, a malignant tumor is continuously heated at about 43.degree. C., for one or two hours, and the above treatment is repeated in preset cycles, whereby the regenerating function of cancer cells is impeded, and simultaneously, most of the cancer cells can be killed (MICROWAVES, October, 1976 issue, page 14). The heating treatment of the type described includes general heating and local heating. Out of these, as the locally heating methods for selectively heating the cancer system and thereabout, there are proposed a method by use of electromagnetic waves, another method by use of electromagnetic induction, a further method by use of ultrasonic waves, etc.
On the other hand, heretofore, the inventors of the present invention have proposed and proceeded with studies on the effectiveness in the case of heatingly treating a cancer in a deep portion of a living body by use of electromagnetic waves. In this case, as for an applicator for heating to deliver the electromagnetic waves into the living body, the inventors have, heretofore, adopted a technique of equipping an electromagnetic lens for the necessity of focusing energy of electromagnetic waves. More specifically, as shown in FIG. 1, an applicator 1 includes: a case body 3 functioning as a waveguide; a feeding section 2 provided on one end portion of the case body 3; and an electromagnetic lens section 4 provided on the other end portion of the case body 3. A solid cooling plate 5 for preventing the surface of living body from being overheated is mounted to an output stage of the electromagnetic lens section 4, and this solid cooling plate 5 may be cooled by a coolant liquid.
However, the above-described conventional example has the following disadvantages.
(1) When the applicator is brought into contact with the living body, a shift in position tends to occur due to the external vibrations.
(2) Air bubbles are produced in the coolant liquid at the applicator portion. The air bubbles form the obstruction, whereby an output of electromagnetic waves is lowered.
(3) The applicator tends to be damaged due to the fluctuations in fluidal pressure of the coolant.
(4) It is difficult to feed the coolant during operation because of the circulation of the coolant in a closed circuit.
(5) Because the applicator, an electromagnetic wave output source and a control section are formed integrally with one another, the apparatus as a whole is rendered large in size and heavy in weight, thus making the handling thereof troublesome.